The source of these data is the U.S. Census Bureau's Residential Construction Branch. The
statistics are based upon reports submitted by local building permit officials in response
to a mail survey. They are obtained using Form C-404, "Report of New Privately-Owned
Residential Building or Zoning Permits Issued." When a report is not received,
missing data is either (1) obtained from the Survey of Use of Permits (SUP) which is used
to collect information on housing starts, or (2) imputed. Data for SUP are available only
for about 850 places for which Census Bureau field representatives list permits.
Imputations are based on the assumption that the ratio of current month authorizations to
those of a year ago should be the same for reporting and nonreporting places.

DEFINITIONS OF TERMS

Residential

1. Dwelling unit (or housing unit): A house or apartment unit intended for occupancy as
separate living quarters and having either:

a. a kitchen or cooking facilities,

or

b. direct access from the outside through a common hall.

Group living quarters, such as dormitories, nursing homes, and barracks are included.

2. Single-family house: A house with one dwelling unit includes semi-detached and row
houses if the units are separated by a ground to roof party wall. Does not include mobile
homes.

3. Two-family house: A house with two dwelling units. If built side-by-side, they do
not have a ground to roof party wall and they generally have a common attic, basement,
heating plant, and other common features.

4. Three-and four-family buildings: Each building contains three or four housing units
having a common basement, heating plant, stairs, water supply and disposal facilities, or
entrance.

5. Five-or-more-family buildings: Each building contains five-or-more housing units
having a common basement, heating plant, stairs, water supply and sewerage disposal
facilities, or entrance. Condominiums and cooperatively owned apartment buildings may fall
into this category.